Rapid Access to Bicyclic δ-Lactones via Carbene- Carbene-Catalyzed Activation of Unsaturated Carboxylic
2.4.5 Characterizations of substrates and products, reference a) Preparations and characterizations of substrates
To a 100 mL of round bottom flask under N2 atmosphere, aldehyde (10 mmol, 1 equiv) was added and dissolved in 50 mL of CH2Cl2, followed by the addition of the phosphorus ylide (10 mmol, 1 equiv). The reaction was kept stirring at RT for 12 h.
Then, the mixture was concentrated under vacuum to remove the CH2Cl2 to give the crude product. Purification by the chromatograph on a silica gel column using hexane : ethyl acetate (3:1) as eluent gave the enone 2-2 as colorless oil.
Note: The β-aldehyde malonate was prepared according to previous report.[23]
(E)-Dimethyl 2-(4-oxo-4-phenylbut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.90 (d, J = 8.0 Hz, 2 H); 7.55 (t, J =7.6 Hz, 1 H); 7.47 (t, J = 8.0 Hz, 2 H); 6.93–6.96 (m, 2 H); 3.76 (s, 6 H); 3.61 (t, J = 7.6 Hz, 1 H); 2.91 (dd, J1 = 7.6 Hz, J2 = 6.0 Hz, 2 H). 13C NMR (100 MHz, CDCl3): δ = 190.2, 168.8, 143.6, 137.5,
132.9, 128.6, 128.5, 128.1, 52.8, 50.5, 31.7 ppm. HRMS(ESI) calcd for C15H17O5
(M+H)+: 277.1076, Found: 277.1078.
(E)-Dimethyl 2-(4-oxo-4-p-tolylbut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.83 (d, J= 8.0 Hz, 2H); 7.27 (d, J= 8.0 Hz, 2H); 6.89–6.99 (m, 2H);
3.82 (s, 6H); 3.60 (t, J= 7.6 Hz, 2H); 2.91 (dd, J= 7.2, 6.0 Hz, 2H); 2.42 (s, 3H). 13C NMR (100 MHz, CDCl3): δ = 189.7, 168.8, 143.8, 143.1, 135.0, 129.3, 128.7, 128.2, 52.8, 50.6, 31.7, 21.7 ppm. HRMS(ESI) calcd for C16H19O5 (M+H)+: 291.1232, Found:
291.1237.
(E)-Dimethyl 2-(4-(4-methoxyphenyl)-4-oxobut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.91–7.95 (m, 2H); 6.87–7.00 (m, 4H); 3.88 (s, 3H); 3.76 (s, 6H); 3.60 (t, J= 7.6 Hz, 2H); 2.91 (t, J= 6.8 Hz, 2H). 13C NMR (100 MHz, CDCl3):
δ = 188.4, 168.8, 163.5, 142.5, 130.9, 130.4, 128.0, 113.8, 55.5, 52.8, 50.6, 31.7 ppm.
HRMS(ESI) calcd for C16H19O6 (M+H)+: 307.1182, Found: 307.1182.
(E)-Dimethyl 2-(4-(4-fluorophenyl)-4-oxobut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.93–7.97 (m, 2H); 7.12–7.17 (m, 2H); 6.93–6.95 (m, 2H); 3.77 (s, 6H); 3.61 (t, J= 7.6 Hz, 2H); 2.90–2.93 (m, 2H). 13C NMR (100 MHz, CDCl3): δ = 188.5, 168.7, 166.9, 164.5, 143.8, 133.9, 133.8, 131.2, 131.1, 127.8, 115.8, 115.6, 52.8, 50.5, 31.7 ppm. HRMS(ESI) calcd for C15H16FO5 (M+H)+: 295.0982, Found: 295.0984.
(E)-Dimethyl 2-(4-(4-chlorophenyl)-4-oxobut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.84–7.88 (m, 2H); 7.43–7.56 (m, 2H); 6.89–6.95 (m, 2H); 3.76 (s, 6H); 3.61 (t, J= 7.6 Hz, 2H); 2.92 (dd, J= 7.2, 5.6 Hz, 2H). 13C NMR (100 MHz, CDCl3): δ = 188.9, 168.7, 144.2, 139.4, 135.8, 130.0, 129.0, 127.7, 52.8, 50.4, 31.7 ppm. HRMS(ESI) calcd for C15H16ClO5 (M+H)+: 311.0686, Found:
311.0692.
(E)-Dimethyl 2-(4-(4-bromophenyl)-4-oxobut-2-enyl)malonate: a white oil; 1H NMR (500 MHz, CDCl3): δ = 7.64-7.82 (m, 2 H); 7.58-7.65 (m, 2 H); 6.85-6.96 (m, 2 H); 3.77 (s, 6 H); 3.60 (t, J= 7.5 Hz, 1 H); 2.92 (dd, J1 = 5.5 Hz, J2= 5.5 Hz, 2 H). 13C NMR (125 MHz, CDCl3): δ = 189.0, 168.2, 144.3, 136.2, 131.9, 130.1, 128.1, 127.7, 52.8, 50.4, 31.7 ppm. HRMS(ESI) calcd for C15H15BrO5Na (M+Na)+: 377.0001, Found:
376.9999.
(E)-Dimethyl 2-(4-(naphthalen-2-yl)-4-oxobut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 8.43 (s, 1H); 7.96–8.02 (m, 2H); 7.87–7.92 (m, 2H);
7.54–7.63 (m, 2H); 7.13 (d, J= 15.6 Hz, 1H); 6.96–7.03 (m, 1H); 3.78 (s, 6H); 3.65 (t, J= 7.6 Hz, 2H); 2.95–2.99 (m, 2H). 13C NMR (100 MHz, CDCl3): δ = 190.0, 168.8, 143.5, 135.5, 134.8, 132.5, 130.3, 129.6, 128.6, 128.5, 128.2, 127.8, 126.8, 124.4, 52.8, 50.6, 31.8 ppm. HRMS(ESI) calcd for C19H19O5 (M+H)+: 327.1232, Found: 327.1242.
(E)-Dimethyl 2-(4-(furan-2-yl)-4-oxobut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.62 (t, J= 0.8 Hz, 1H); 7.25 (d, J= 3.6 Hz, 1H); 6.99–7.06 (m, 1H); 6.87 (d, J= 19.6 Hz, 1H); 6.56 (dd, J= 3.6, 1.6 Hz, 1H); 3.76 (s, 6H); 3.60 (t, J=
7.2 Hz, 2H); 2.90 (t, J= 7.2 Hz, 2H). 13C NMR (100 MHz, CDCl3): δ = 177.5, 168.8, 153.1, 146.8, 143.0, 127.3, 118.0, 112.5, 52.8, 50.5, 31.6 ppm. HRMS(ESI) calcd for C13H15O6 (M+H)+: 267.0863, Found: 267.0864.
(E)-Dimethyl 2-(4-oxo-4-(thiophen-2-yl)but-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.75 (d, J= 3.6 Hz, 1H); 7.67 (d, J= 4.8 Hz, 1H); 7.15–
7.17 (m, 1H); 6.95–7.03 (m, 1H); 6.87 (d, J= 15.2 Hz, 1H); 3.76 (s, 6H); 3.61 (t, J= 7.2 Hz, 2H); 2.91 (t, J= 7.2 Hz, 2H). 13C NMR (100 MHz, CDCl3): δ = 181.7, 168.8, 144.8, 142.9, 134.1, 132.2, 128.3, 127.7, 52.8, 50.5, 31.6 ppm. HRMS(ESI) calcd for C13H15O5S (M+H)+: 283.0640, Found: 283.0644.
(E)-Dimethyl 2-(3-methyl-4-oxo-4-phenylbut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.62–7.64 (m, 2H); 7.49–7.53 (m, 1H); 7.39–7.43 (m, 2H); 6.14–6.18 (m, 1H); 3.75 (s, 6H); 3.51 (t, J= 7.6 Hz, 2H); 2.88 (t, J= 7.6 Hz, 2H);
2.00 (s, 3H). 13C NMR (100 MHz, CDCl3): δ = 198.4, 168.9, 139.4, 138.8, 138.0, 131.8, 129.5, 128.1, 52.7, 50.7, 28.3, 12.8 ppm. HRMS(ESI) calcd for C16H19O5 (M+H)+:
(E)-Dimethyl 2-(2-(1-oxo-3,4-dihydronaphthalen-2(1H)-ylidene)ethyl)malonate:
a colorless oil; 1H NMR (400 MHz, CDCl3): δ = 8.05-8.15 (m, 1 H); 7.46-7.55 (m, 1 H); 7.30-7.40 (m, 1 H); 7.22-7.28 (m, 1 H); 6.74-6.82 (m, 1 H); 3.73 (s, 3 H); 3.58 (t, J
= 7.6 Hz, 1 H); 2.92-3.02 (m, 2 H); 2.72-2.88 (m, 4 H). 13C NMR (100 MHz, CDCl3):
δ = 187.1, 169.0, 143.7, 137.6, 133.7, 133.3, 128.3, 128.2, 126.7, 52.7, 50.8, 29.0, 27.6, 25.8 ppm. HRMS(ESI) calcd for C17H19O5 (M+H)+: 303.1232, Found: 303.1233.
(E)-Dimethyl 2-(4-oxopent-2-enyl)malonate:
a colorless oil; 1H NMR (500 MHz, CDCl3): δ = 6.73 (dt, J = 16.0, 7.0 Hz, 1 H), 6.13 (dt, J = 16.0, 1.4 Hz, 1 H), 3.76 (s, 6 H), 3.75 (d, J = 7.6 Hz, 1 H), 3.55 (t, J = 7.4 Hz, 1 H), 2.82 (td, J = 7.2, 1.5 Hz, 2H), 2.24 (s, 3H). 13C NMR (125 MHz, CDCl3): δ = 197.9, 168.6 (x2), 142.4, 133.1, 52.7, 50.3, 31.2, 27.0 ppm. HRMS(ESI) calcd for C10H15O5 (M+H)+: 215.0919, Found: 215.0911.
(E)-Diethyl 2-(4-oxo-4-phenylbut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.91 (d, J = 7.2 Hz, 2 H); 7.55 (t, J =7.2, 1 H); 7.47 (t, J = 8.0 Hz, 2 H);
6.95–6.97 (m, 2 H); 4.18–4.25 (m, 4 H); 3.57 (t, J = 7.6 Hz, 1 H); 2.89–2.93 (m, 2 H);
1.27 (t, J = 7.2 Hz, 6 H). 13C NMR (100 MHz, CDCl3): δ = 190.2, 168.4, 143.9, 137.6, 132.9, 128.6, 128.5, 128.1, 61.7, 50.8, 31.7, 14.1 ppm. HRMS(ESI) calcd for C17H21O5
(M+H)+: 305.1389, Found: 305.1390.
(E)-Dibenzyl 2-(4-oxo-4-phenylbut-2-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.85 (d, J = 7.2 Hz, 2 H); 7.55 (t, J =7.6, 1 H); 7.44 (t, J = 8.0 Hz, 2 H); 7.36 (t, J = 4.8 Hz, 1 H); 7.26–7.32 (m, 9 H); 6.86–6.96 (m, 2 H); 5.12–5.19 (m, 4 H); 3.69 (t, J = 7.2 Hz, 1 H); 2.93 (dd, J1 = 7.6 Hz, J2 = 5.6 Hz, 2 H). 13C NMR (100 MHz, CDCl3): δ = 190.1, 168.1, 143.5, 137.5, 135.1, 132.8, 128.6, 128.5, 128.4, 128.3, 128.1, 67.5, 50.8, 31.7 ppm. HRMS(ESI) calcd for C27H25O5 (M+H)+: 429.1702, Found:
429.1701.
(E)-Dimethyl 2-(5-oxo-5-phenylpent-3-enyl)malonate: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.92 (d, J = 7.2 Hz, 2 H); 7.57 (t, J =7.2, 1 H); 7.47 (t, J = 7.6 Hz, 2
J2 = 6.8 Hz, 2 H); 2.15 (dd, J1 = 14.4 Hz, J2 = 7.6 Hz, 2 H). 13C NMR (100 MHz, CDCl3):
δ = 190.5, 169.4, 146.9, 137.7, 132.8, 128.6, 128.5, 126.9, 52.6, 50.9, 30.2, 27.2 ppm.
HRMS(ESI) calcd for C16H19O5 (M+H)+: 291.1232, Found: 291.1231.
(E)-6-Nitro-1-phenylhex-2-en-1-one: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 7.93–7.96 (m, 2H); 7.56–7.60 (m, 1H); 7.47–7.50 (m, 2H); 6.94–7.03 (m, 2H); 4.45 (t, J= 6.4 Hz, 2H); 2.43–2.48 (m, 2H); 2.23–2.30 (m, 2H). 13C NMR (100 MHz, CDCl3):
δ = 190.1, 145.5, 137.6, 133.0, 128.7, 128.6, 127.5, 74.6, 29.2, 25.8 ppm. HRMS(ESI) calcd for C12H14NO3 (M+H)+: 220.0974, Found: 220.0974.
(E)-1-(furan-3-yl)-4,4-Dimethyl-6-nitrohex-2-en-1-one: a yellow oil; 1H NMR (400 MHz, CDCl3): δ = 8.09 (s, 1 H); 7.49 (t, J = 3.2 Hz, 1 H); 6.95 (d, J = 15.6 Hz, 1 H);
6.85–6.85 (m, 1H); 6.51 (d, J = 15.6 Hz, 1 H); 4.33–4.37 (m, 2 H); 2.21–2.25 (m, 2 H);
1.21 (s, 6 H). 13C NMR (100 MHz, CDCl3): δ = 183.9, 153.5, 147.4, 144.4, 128.1, 124.3, 128.1, 124.3, 109.1, 72.4, 38.6, 36.0, 26.4 ppm. HRMS(ESI) calcd for C12H16NO4
(M+H)+: 238.1079, Found: 238.1079.
b) Characterizations of products
(4aS,7R,7aR)-Dimethyl 1-oxo-3,7-diphenyl-4a,5,7,7a-tetrahydrocyclo-
penta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.70, CHCl3) = -16.8;
1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 2.4 Hz, 2 H); 7.24–7.39 (m, 8 H); 5.56 (d, J = 3.2 Hz, 1 H); 4.70 (d, J = 8.8 Hz, 1 H); 3.71 (s, 3 H); 3.52–3.61 (m, 2 H); 3.13 (m, 4 H); 2.27 (dd, J1 = 12.0 Hz, J2 = 4.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.6, 170.2, 168.4, 149.2, 137.3, 132.2, 129.2, 128.7, 128.5, 128.3, 127.8, 124.8, 102.2, 65.1, 53.7, 53.1, 52.3, 47.6, 41.3, 36.7 ppm. IR (film): νmax 2952, 1731, 1515, 1425, 1272, 1211, 1008 cm-1. HRMS (ESI): C24H23O6 [M+H]+ calcd: 407.1495, found: 407.1492; 96:4 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 13.4 min, tr (minor) = 16.6 min.
(4aS,7R,7aR)-Dimethyl 7-(4-methoxyphenyl)-1-oxo-3-phenyl-4a,5,7,7a-tetra- hydrocyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.44, CHCl3)
= -40.5; 1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 2.0 Hz, 2 H); 7.36–
7.39 (m, 3 H); 7.25 (d, J = 9.2 Hz, 2 H); 6.83 (d, J = 8.0 Hz, 2 H); 5.53 (d, J = 3.2 Hz, 1 H); 4.61 (d, J = 9.6 Hz, 1 H); 3.77 (s, 3 H); 3.71 (s, 3 H); 3.49–3.59 (m, 2 H); 3.20 (s,
3 H); 3.11 (dd, J1 = 14.0 Hz, J2 = 7.2 Hz, 1 H); 2.68 (dd, J1 = 14.0 Hz, J2 = 4.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.7, 170.4, 168.4, 159.1, 149.1, 132.2, 129.9, 129.2, 129.0, 128.5, 124.8, 113.6, 102.4, 64.8, 55.2, 53.1, 53.0, 52.4, 47.6, 41.1, 36.4 ppm. IR (film): νmax 2952, 1757, 1729, 1515, 1436, 1221, 1127, 1025, 929 cm-1. HRMS (ESI): C25H25O7 [M+H]+ calcd: 437.1600, found: 437.1613; 95:5 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 17.7 min, tr
(minor) = 21.5 min.
(4aS,7R,7aR)-Dimethyl 7-(4-fluorophenyl)-1-oxo-3-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.90, CHCl3) = -22.9; 1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 2.4 Hz, 2 H); 7.34–
7.41 (m, 3 H); 7.32 (dd, J1 = 8.8 Hz, J2 = 5.2 Hz, 2 H); 6.99 (t, J = 8.8 Hz, 2 H); 5.55 (d, J = 3.2 Hz, 1 H); 4.64 (d, J = 10.0 Hz, 1 H); 3.72 (s, 3 H); 3.56–3.62 (m, 1 H); 3.51 (t, J = 8.8 Hz, 1 H); 3.20 (s, 3 H); 3.11 (dd, J1 = 14.0 Hz, J2 = 7.2 Hz, 1 H) ; 2.27 (dd, J1 = 14.0 Hz, J2 = 4.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.3, 168.1, 149.2, 132.7, 132.6, 132.1, 130.5, 130.4, 129.3, 128.6, 124.8, 115.2, 115.0, 102.2, 64.8, 53.1, 52.9, 52.4, 47.5, 41.1, 36.5 ppm. IR (film): νmax 2954, 1762, 1729, 1515, 1437, 1275, 1215, 1016, 929 cm-1. HRMS (ESI): C24H22FO6 [M+H]+ calcd: 425.1400, found:
425.1383; 95:5 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7
(4aS,7R,7aR)-Dimethyl 7-(4-chlorophenyl)-1-oxo-3-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.76, CHCl3) = -41.2; 1H NMR (400 MHz, CDCl3): δ = 7.58 (dd, J1 = 8.0 Hz, J2 = 2.4 Hz, 2 H); 7.35 – 7.39 (m, 3 H); 7.28 (s, 4 H); 5.55 (d, J = 3.2 Hz, 1 H); 4.62 (d, J = 9.6 Hz, 1 H); 3.72 (s, 3 H); 3.56–3.61 (m, 1 H); 3.50 (t, J = 8.8 Hz, 1 H); 3.21 (s, 3 H); 3.10 (dd, J1 = 14.0 Hz, J2 = 7.6 Hz, 1 H) ; 2.27 (dd, J1 = 14.0 Hz, J2 = 4.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.4, 170.2, 168.1, 149.1, 135.5, 133.7, 132.0, 130.2, 129.3, 128.6, 128.4, 124.8, 102.2, 64.8, 53.1, 53.0, 52.1, 47.3, 41.2, 36.5 ppm. IR (film): νmax 2953, 1762, 1729, 1526, 1436, 1255, 1015, 928 cm-1. HRMS (ESI): C24H22ClO6 [M+H]+ calcd:
441.1105, found: 441.1102; 96:4 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 13.5 min, tr (minor) = 18.7 min.
(4aS,7R,7aR)-Dimethyl 7-(4-bromophenyl)-1-oxo-3-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 2.12, CHCl3) = -47.3; 1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 2.8 Hz, 2 H); 7.36–
7.44 (m, 5 H); 7.22 (d, J = 8.4 Hz, 2 H); 5.55 (d, J = 3.2 Hz, 1 H); 4.60 (d, J = 10.0 Hz,
1 H); 3.72 (s, 3 H); 3.57–3.60 (m, 1 H); 3.50 (t, J = 8.8 Hz, 1 H); 3.22 (s, 3 H); 3.10 (dd, J1 = 14.0 Hz, J2 = 7.2 Hz, 1 H) ; 2.26 (dd, J1 = 14.0 Hz, J2 = 4.4 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.4, 170.2, 168.0, 149.1, 136.1, 132.0, 131.4, 130.5, 129.3, 128.6, 128.4, 121.9, 102.2, 64.7, 53.1, 53.0, 52.5, 47.3, 41.2, 36.5 ppm. IR (film): νmax
2954, 1767, 1730, 1558, 1539, 1275, 1215, 1011, 929 cm-1. HRMS (ESI): C24H22BrO6
[M+H]+ calcd: 485.0600, found: 485.0587; 97:3 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 14.1 min, tr (minor) = 19.6 min.
(4aS,7R,7aR)-Dimethyl 7-(4-nitrophenyl)-1-oxo-3-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.41, CHCl3) = -58.9; 1H NMR (400 MHz, CDCl3): δ = 8.17 (d, J = 8.8 Hz, 2 H); 7.59 (dd, J1 = 8.0 Hz, J2 = 4.4 Hz, 2 H); 7.55 (d, J = 8.8 Hz, 2 H); 7.37–7.42 (m, 3 H); 5.59 (d, J = 3.2 Hz, 1 H); 4.72 (d, J = 10.0 Hz, 1 H); 3.75 (s, 3 H); 3.63–3.67 (m, 1 H); 3.58 (t, J = 9.6 Hz, 1 H); 3.22 (s, 3 H); 3.13 (dd, J1 = 14.0 Hz, J2 = 7.6 Hz, 1 H); 2.29 (dd, J1 = 14.0 Hz, J2 = 4.8 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.0, 169.9, 167.7, 149.1, 147.4, 144.5, 131.9, 129.9, 129.4, 128.6, 124.8, 123.3, 101.9, 64.8, 53.3, 53.2, 52.6, 47.1, 41.4, 36.4 ppm. IR (film): νmax 2955, 1730, 1526, 1424, 1350, 1024, 925 cm-1. HRMS (ESI):
C24H22NO8 [M+H]+ calcd: 452.1345, found: 452.1348; 97:3 er as determined by HPLC
(Chiralcel IB, 85:15 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 23.4 min, tr (minor) = 42.9 min.
(4aS,7R,7aR)-Dimethyl 1-oxo-3-phenyl-7-o-tolyl-4a,5,7,7a-tetrahydrocyclopenta- [c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.25, CHCl3) = +13.6; 1H NMR (400 MHz, CDCl3): δ = 7.60 (dd, J1 = 8.0 Hz, J2 = 2.0 Hz, 2 H); 7.35–7.40 (m, 3 H); 7.08–7.17 (m, 3 H); 7.04 (d, J = 8.0 Hz, 1 H); 5.58 (d, J = 4.0 Hz, 1 H); 5.18 (d, J
= 6.8 Hz, 1 H); 3.67 (s, 3 H); 3.58–3.60 (m, 1 H); 3.36 (t, J = 7.6 Hz, 1 H); 3.14 (dd, J1
= 13.6 Hz, J2 = 6.8 Hz, 1 H) ; 3.08 (s, 3 H); 2.47 (s, 3 H); 2.67 (dd, J1 = 14.0 Hz, J2 = 5.6 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.6, 169.9, 168.6, 149.7, 138.0, 137.9, 132.3, 130.4, 129.2, 128.5, 127.3, 126.8, 126.0, 124.8, 101.6, 65.6, 53.1, 52.2, 50.8, 48.8, 41.8, 37.3, 20.3 ppm. IR (film): νmax 2952, 1734, 1434, 1260, 1216, 1125, 1046, 936, 884 cm-1. HRMS (ESI): C25H25O6[M+H]+ calcd: 421.1646, found: 421.1646; 98:2 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major)
= 12.0 min, tr (minor) = 14.5 min.
(4aS,7R,7aR)-Dimethyl 7-(3-bromophenyl)-1-oxo-3-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.45, CHCl3) = -21.6; 1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 2.4 Hz, 2 H); 7.48 (s, 1 H); 7.36–7.40 (m, 3 H);7.27 (d, J = 8.4 Hz, 2 H); 7.18 (t, J = 8.0 Hz, 1 H); 5.57 (d, J
= 3.6 Hz, 1 H); 4.63 (d, J = 9.2 Hz, 1 H); 3.72 (s, 3 H); 3.59–3.62 (m, 1 H); 3.50 (t, J = 8.8 Hz, 1 H); 3.20 (s, 3 H); 3.10 (dd, J1 = 14.0 Hz, J2 = 6.8 Hz, 1 H) ; 2.24 (dd, J1 = 14.0 Hz, J2 = 4.8 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.2, 170.1, 168.0, 149.2, 139.7, 132.1, 131.9, 130.9, 129.8, 129.3, 128.6, 127.3, 124.8, 122.3, 102.0, 64.9, 53.2, 53.1, 52.4, 47.4, 41.3, 36.6 ppm. IR (film): νmax 2952, 1761, 1729, 1525, 1436, 1215, 1124, 1024, 928 cm-1. HRMS (ESI): C24H22BrO6Na [M+Na]+ calcd: 485.0600, found:
485.0603; 96:4 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 13.5 min, tr (minor) = 17.5 min.
(4aS,7R,7aR)-Dimethyl 7-(naphthalen-2-yl)-1-oxo-3-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.68, CHCl3) = -71.8; 1H NMR (400 MHz, CDCl3): δ = 7.76–7.82 (m, 4 H); 7.61 (dd, J1 = 8.0 Hz, J2 = 2.0 Hz, 2 H); 7.36–7.47 (m, 5 H); 5.60 (d, J = 2.0 Hz, 1 H); 4.86 (d, J = 8.4 Hz, 1 H);
3.72 (s, 3 H); 3.67–3.70 (m, 2 H); 3.16 – 3.20 (m, 1 H); 3.02 (s, 3 H); 2.31 (dd, J1 = 14.0 Hz, J2 = 3.6 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.3, 168.3, 149.2,
124.8, 102.0, 65.0, 53.9, 53.1, 52.3, 47.8, 41.4, 36.7 ppm. IR (film): νmax 2954, 1761, 1725, 1525, 1436, 1124, 1024, 928 cm-1. HRMS (ESI): C28H25O6 [M+H]+ calcd:
457.1651, found: 457.1651; 96:4 er as determined by HPLC (Chiralcel IA, 80:20 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 40.6 min, tr (minor) = 22.5 min.
(4aS,7S,7aR)-Dimethyl 7-(furan-2-yl)-1-oxo-3-phenyl-4a,5,7,7a-tetrahydrocyclo- penta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.60, CHCl3) = -11.0;
1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 2.4 Hz, 2 H); 7.33–7.40 (m, 4 H); 6.30 (s, 2 H); 5.55 (d, J = 2.4 Hz, 1 H); 4.73 (d, J = 7.6 Hz, 1 H); 3.69 (s, 3 H); 3.57–3.60 (m, 2 H); 3.44 (s, 3 H); 3.08–3.13 (m, 1 H); 2.19 (dd, J1 = 14.0 Hz, J2 = 4.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 170.1, 169.8, 168.0, 151.0, 148.9, 142.3, 132.1, 129.2, 128.5, 124.7, 110.6, 108.8, 101.9, 63.3, 53.1, 53.0, 48.1, 46.1, 41.0, 36.0 ppm. IR (film): νmax 2954, 1734, 1554, 1527, 1424, 1215, 1013, 929 cm-1. HRMS (ESI):
C22H21O7 [M+H]+ calcd: 397.1287, found: 397.1283; 96:4 er as determined by HPLC (Chiralcel ID, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 60.1 min, tr (minor) = 72.5 min.
(4aS,7S,7aR)-Dimethyl 1-oxo-3-phenyl-7-(thiophen-2-yl)-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.95, CHCl3) = -21.7; 1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 2.4 Hz, 2 H); 7.34–
7.39 (m, 3 H); 7.20 (dd, J1 = 4.8 Hz, J2 = 0.8 Hz, 1 H); 7.03 (d, J = 3.6 Hz, 1 H); 6.94 (dd, J1 = 5.2 Hz, J2 = 3.6 Hz, 1 H); 5.54 (d, J = 3.6 Hz, 1 H); 4.86 (d, J = 8.8 Hz, 1 H); 3.73 (s, 3 H); 3.56–3.59 (m, 2 H); 3.33 (s, 3 H); 3.10–3.15 (m, 1 H); 2.30 (dd, J1 = 14.0 Hz, J2 = 3.2 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.3, 170.1, 167.8, 149.0, 139.6, 132.0, 129.3, 128.6, 126.8, 126.6, 125.1, 124.8, 102.2, 64.8, 53.1, 52.7, 49.3, 48.8, 40.8, 36.1 ppm. IR (film): νmax 2952, 1762, 1730, 1558, 1517, 1434, 1024, 929 cm-1. HRMS (ESI): C22H21O6S [M+H]+ calcd: 413.1059, found: 413.1059; 95:5 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 15.2 min, tr (minor) = 19.2 min.
(4aS,7S,7aR)-Dimethyl 1-oxo-3-phenyl-7-styryl-4a,5,7,7a-tetrahydrocyclopenta- [c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.06, CHCl3) = -38.7; 1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 2.0 Hz, 2 H); 7.20–7.40 (m, 8 H); 6.64 (d, J = 15.6 Hz, 1 H); 6.09 (dd, J1 = 16.0 Hz, J2 = 8.8 Hz, 1 H); 5.50 (d, J =
2.8 Hz, 1 H); 3.97 (t, J = 9.2 Hz, 1 H); 3.71 (s, 3 H); 3.65 (s, 3 H); 3.42–3.47 (m, 1 H);
3.24 (t, J = 9.2 Hz, 1 H); 2.97 (dd, J1 = 14.0 Hz, J2 = 8.0 Hz, 1 H); 2.37 (dd, J1 = 10.0 Hz, J2 = 4.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.3, 170.5, 168.1, 148.6, 136.6, 134.4, 132.2, 129.2, 128.6, 128.5, 127.7, 126.6, 125.2, 124.8, 102.4, 63.5, 53.0, 52.8, 52.4, 47.6, 41.0, 36.0 ppm. IR (film): νmax 2954, 2321, 1734, 1558, 1517, 1424, 928 cm-1. HRMS (ESI): C26H24O6Na [M+Na]+ calcd: 455.1471, found: 455.1475; 94:6 er as determined by HPLC (Chiralcel IA, 80:20 hexanes/i-PrOH, 0.7 mL/min), tr (major)
= 17.3 min, tr (minor) = 13.6 min.
(4aS,7S,7aR)-7-Ethyl-6,6-dimethyl 1-oxo-3-phenyl-4a,5,7,7a-tetrahydrocyclo- penta[c]pyran-6,6,7(1H)-tricarboxylate: a yellow oil; [α]D 23 (c 1.25, CHCl3) = +10.2;
1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 2.4 Hz, 2 H); 7.34–7.40 (m, 3 H); 5.62 (d, J = 4.4 Hz, 1 H); 4.16–4.25 (m, 3 H); 3.73–3.76 (m, 3 H); 3.67–3.72 (m, 3 H); 3.31 – 3.39 (m, 1 H); 2.84 (dd, J1 = 13.2 Hz, J2 = 7.2 Hz, 1 H); 2.18 (dd, J1 = 13.2 Hz, J2 = 8.4 Hz, 1 H); 1.28 (t, J = 7.2 Hz, 3 H). 13C NMR (100 MHz, CDCl3): δ = 171.0, 170.4, 169.8, 168.3, 149.1, 132.0, 129.3, 128.5, 124.7, 100.6, 62.4, 61.7, 54.3, 53.3, 53.0, 43.8, 42.2, 35.8, 14.0 ppm. IR (film): νmax 2952, 2321, 1731, 1518, 1437, 1340, 1112, 928 cm-1. HRMS (ESI): C21H22O8Na [M+Na]+ calcd: 425.1212, found:
425.1211; 94:6 er as determined by HPLC (Chiralcel IA, 95:5 hexanes/i-PrOH, 0.7
(4aS,7S,7aR)-Dimethyl 7-ethyl-1-oxo-3-phenyl-4a,5,7,7a-tetrahydrocyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.06, CHCl3) = +17.5; 1H NMR (400 MHz, CDCl3): δ = 7.58 (dd, J1 = 8.4 Hz, J2 = 2.8 Hz, 2 H); 7.34–7.39 (m, 3 H); 5.48 (d, J = 3.2 Hz, 1 H); 3.74 (s, 3 H); 3.66 (s, 3 H); 3.34–
3.39 (m, 1 H); 3.13–3.19 (m, 1 H); 2.92 (t, J = 8.4 Hz, 1 H); 2.81 (dd, J1 = 13.6 Hz, J2
= 7.6 Hz, 1 H); 2.23 (dd, J1 = 10.0 Hz, J2 = 5.2 Hz, 1 H), 1.52–1.62 (m, 2 H); 1.03 (t, J = 7.6 Hz, 3 H). 13C NMR (100 MHz, CDCl3): δ = 171.8, 171.0, 169.7, 148.6, 132.3, 129.1, 128.5, 124.7, 102.4, 62.6, 52.9, 52.6, 50.6, 47.1, 41.5, 35.7, 24.5, 12.4 ppm. IR (film): νmax 2954, 1734, 1558, 1525, 1437, 1419, 1018, 928 cm-1. HRMS (ESI):
C20H23O6 [M+H]+ calcd: 359.1495, found: 359.1497; 75:25 er as determined by HPLC (Chiralcel IA, 80:20 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 14.1 min, tr (minor) = 10.2 min.
(4aS,7aS)-Dimethyl 1-oxo-3-phenyl-4a,5,7,7a-tetrahydrocyclopenta[c]pyran- 6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.34, CHCl3) = -1.1; 1H NMR (400 MHz, CDCl3): δ = 7.59 (dd, J1 = 8.0 Hz, J2 = 4.4 Hz, 2 H); 7.34–7.40 (m, 3 H); 5.63 (d, J = 4.4 Hz, 1 H); 3.77 (s, 3 H); 3.70 (s, 3 H); 3.14–3.18 (m, 2 H); 2.78–2.90 (m, 2 H); 2.62
(dd, J1 = 13.6 Hz, J2 = 7.2 Hz, 1 H); 2.33 (dd, J1 = 13.6 Hz, J2 = 8.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 172.0, 171.2, 169.4, 149.0, 132.2, 129.2, 128.5, 124.7, 101.5, 58.8, 53.1, 53.0, 41.5, 41.0, 36.8 ppm. IR (film): νmax 2952, 1734, 1549, 1525, 1437, 1023, 928 cm-1. HRMS (ESI): C18H19O6 [M+H]+ calcd: 331.1182, found: 331.1174;
53:47 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr
(major) = 15.0 min, tr (minor) = 16.1 min.
(4aS,7R,7aR)-Dimethyl 3-(4-methoxyphenyl)-1-oxo-7-phenyl-4a,5,7,7a- tetrahydrocyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 0.5, CHCl3) = -80.3; 1H NMR (400 MHz, CDCl3): δ = 7.53 (dd, J1 = 6.8Hz, J2 = 1.6 Hz, 2 H); 7.18–7.36 (m, 5 H); 6.89 (dd, 2 H, J = 6.8, 2.0 Hz, 2 H); 5.42 (d, J = 3.2 Hz, 1 H);
4.70 (d, J = 8.8 Hz, 1 H); 3.82 (s, 3 H); 3.71 (s, 3 H); 3.48–3.64 (m, 2 H); 3.13 (s, 3 H);
3.04–3.15 (m, 1 H); 2.26 (dd, J = 14.0, 4.4 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.2, 168.5, 160.4, 149.0, 137.4, 128.7, 128.2, 127.7, 126.2, 124.7, 113.9, 100.2, 65.1, 55.3, 53.6, 53.0, 52.2, 47.6, 41.3, 36.6 ppm. IR (film): νmax 2954, 2400, 1759, 1728, 1609, 1513, 1435, 1248, 1177, 1030, 928 cm-1. HRMS (ESI): C25H25O7 [M+H]+ calcd: 437.1600, found: 437.1602; 94:6 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 18.8 min, tr (minor) = 21.2 min.
(4aS,7R,7aR)-Dimethyl 1-oxo-7-phenyl-3-p-tolyl-4a,5,7,7a-tetrahydrocyclo- penta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 0.5, CHCl3) = -52.9;
1H NMR (400 MHz, CDCl3): δ = 7.48 (d, J = 8.0 Hz, 2 H); 7.20–7.35 (m, 5 H); 7.18 (d, J = 8.0 Hz, 2 H); 5.51 (d, J = 3.2 Hz, 1 H); 4.70 (d, J = 8.8 Hz, 1 H); 3.70 (s, 3 H);
3.49–3.64 (m, 2 H); 3.13 (s, 3 H); 3.02–3.13 (m, 3 H); 2.36 (s, 3 H); 2.26 (dd, J = 14.0, 4.4 Hz, 1 H. 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.2, 168.4, 149.2, 139.2, 137.4, 129.3, 129.2, 128.7, 128.2, 127.7, 124.7, 101.2, 65.0, 53.6, 53.0, 52.2, 47.6, 41.2, 36.6, 21.2 ppm. IR (film): νmax 2952, 1730, 1570, 1533, 1272, 1126, 1042, 1017, 930 cm-1. HRMS (ESI): C25H25O6 [M+H]+ calcd: 421.1651, found: 421.1652; 96:4 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 13.9 min, tr (minor) = 16.1 min.
(4aS,7R,7aR)-Dimethyl 3-(4-fluorophenyl)-1-oxo-7-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.00, CHCl3) = -19.9; 1H NMR (400 MHz, CDCl3): δ = 7.54–7.62 (m, 2 H); 7.21–7.38 (m, 5 H); 7.03 – 7.10 (m, 2 H); 5.49 (d, J = 3.2 Hz, 1 H); 4.69 (d, J = 8.8 Hz, 1 H); 3.71 (s, 3 H); 3.52 –
3.65 (m, 2 H); 3.08–3.16 (m, 4 H); 2.26 (dd, J = 14.0, 4.4 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.1, 168.1, 163.3 (J = 248 Hz), 148.4, 137.2, 128.7, 128.39, 128.36, 128.2, 127.8, 126.8, 126.7, 115.7, 115.4, 101.9, 65.0, 53.6, 53.0, 52.3, 47.5, 41.2, 36.6 ppm. IR (film): νmax 2952, 1767, 1730, 1558, 1510, 1272, 1159, 1024, 929 cm-1. HRMS (ESI): C24H22O6F [M+H]+ calcd: 425.1400, found: 425.1401; 96:4 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 13.8 min, tr (minor) = 15.7 min.
(4aS,7R,7aR)-Dimethyl 3-(4-chlorophenyl)-1-oxo-7-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 0.5, CHCl3) = -56.7; 1H NMR (400 MHz, CDCl3): δ = 7.53 (dd, J = 6.8, 1.6 Hz, 2 H); 7.20–7.40 (m, 7 H); 5.56 (d, J = 2.8 Hz, 1 H); 4.68 (d, J = 8.8 Hz, 1 H); 3.71 (s, 3 H); 3.52–3.68 (m, 2 H); 3.06–3.18 (m, 4 H); 2.25 (dd, J1 = 14.0 Hz, J2 = 4.4 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.1, 168.0, 148.2, 137.2, 135.1, 130.6, 128.7, 128.6, 128.2, 127.8, 126.0, 102.6, 65.0, 53.6, 53.0, 52.3, 47.5, 41.2, 36.6 ppm. IR (film): νmax 2954, 1728, 1523, 1435, 1012, 928 cm-1. HRMS (ESI): C24H22O6Cl [M+H]+ calcd: 441.1105, found:
441.1096; 96:4 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 15.3 min, tr (minor) = 16.9 min.
(4aS,7R,7aR)-Dimethyl 3-(4-bromophenyl)-1-oxo-7-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.00, CHCl3) = +29.2; 1H NMR (400 MHz, CDCl3): δ = 7.48 (dd, J = 18.8, 8.8 Hz, 4 H); 7.23–7.34 (m, 5 H); 5.57 (d, J = 3.2 Hz, 1 H); 4.68 (d, J = 8.4 Hz, 1 H); 3.71 (s, 3 H); 3.50–3.63 (m, 2 H); 3.13 (s, 3 H); 3.08–3.16 (m, 1 H); 2.25 (dd, J = 13.6, 8.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.1, 168.0, 148.3, 137.2, 131.7, 131.1, 128.7, 128.3, 127.8, 126.3, 123.4, 102.7, 65.0, 53.7, 53.0, 52.3, 47.5, 41.1, 36.7 ppm. IR (film): νmax 2954, 1762, 1729, 1515, 1437, 1275, 1215, 1016, 929 cm-1. IR (film): νmax 2952, 1728, 1523, 1425, 1008, 925 cm-1. HRMS (ESI): C24H22O6Br [M+H]+ calcd: 485.0600, found:
485.0602; 96:4 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 20.7 min, tr (minor) = 23.2 min.
(4aS,7R,7aR)-Dimethyl 3-(naphthalen-2-yl)-1-oxo-7-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.00, CHCl3) = -62.5; 1H NMR (400 MHz, CDCl3): δ = 8.14–8.20 (m, 1 H); 7.78–7.90 (m, 3 H); 7.63
J = 3.2 Hz, 1 H); 4.74 (d, J = 8.8 Hz, 1 H); 3.70 (s, 3 H); 3.56–3.68 (m, 2 H); 3.08–3.20 (m, 4 H); 2.32 (dd, J1 = 13.6 Hz, J2 = 4.4 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.0, 168.4, 149.1, 137.4, 133.5, 133.1, 129.1, 128.7, 128.6, 128.2, 127.7, 127.6, 126.7, 126.6, 124.3, 122.0, 102.6, 65.1, 53.7, 53.0, 52.2, 47.7, 41.3, 36.7 ppm. IR (film):
νmax 2952, 1756, 1729, 1515, 1436, 1192, 1130, 1045, 929 cm-1. HRMS(ESI) calcd for
C28H25O6 (M+H)+: 457.1651, Found: 457.1649; 96:4 er as determined by HPLC (Chiralcel IC, 80:20 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 26.8 min, tr (minor) = 44.6 min.
(4aS,7R,7aR)-Dimethyl 3-(furan-2-yl)-1-oxo-7-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 0.5, CHCl3) = -22.9; 1H NMR (400 MHz, CDCl3): δ = 7.38–7.44 (m, 1 H); 7.22 – 7.35 (m, 5 H); 6.59 (d, J = 3.6 Hz, 1 H); 6.44 (dd, J = 3.6, 2.0 Hz, 1 H);5.54 (d, J = 3.2 Hz, 1 H); 4.66 (d, J
= 8.8 Hz, 1 H); 3.71 (s, 3 H); 3.50–3.65 (m, 2 H); 3.05–3.18 (m, 4 H); 2.26 (dd, J = 13.6, 4.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.2, 167.6, 146.6, 143.2, 142.0, 137.1, 128.7, 128.2, 127.8, 111.5, 108.1, 100.3, 65.0, 53.7, 53.0, 52.3, 47.8, 41.1, 36.2 ppm. IR (film): νmax 2954, 1728, 1524, 1425, 1012, 928 cm-1. HRMS(ESI) calcd for C22H21O7 (M+H)+: 457.1651, Found: 457.1649; 96:4 er as determined by HPLC
(Chiralcel IB, 97:3 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 21.0 min, tr (minor) = 24.9 min.
(4aS,7R,7aR)-Dimethyl 1-oxo-7-phenyl-3-(thiophen-2-yl)-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 0.5, CHCl3) = -111.5; 1H NMR (400 MHz, CDCl3): δ = 7.22–7.34 (m, 7 H); 7.02 (dd, J = 5.2, 4.0 Hz, 1 H); 5.44 (d, J = 3.2 Hz, 1 H); 4.69 (d, J = 8.8 Hz, 1 H); 3.73 (s, 3 H); 3.50–3.62 (m, 2 H); 3.13 (s, 3 H); 3.09 (dd, J1 = 14.0 Hz, J2 = 7.2 Hz, 1 H); 2.26 (dd, J = 13.6, 4.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ =171.4, 170.1, 167.8, 145.0, 137.3, 135.6, 128.7, 128.2, 127.7, 127.6, 125.9, 124.9, 101.1, 65.0, 53.7, 53.0, 52.3, 47.7, 41.2, 36.6 ppm.
IR (film): νmax 2954, 1728, 1518, 1437, 1022, 928 cm-1. HRMS(ESI) calcd for C22H21O6S (M+H)+: 413.1059, Found: 413.1057; 95:5 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 14.4 min, tr (minor) = 18.2 min.
(4aR,7R,7aR)-Dimethyl 4-methyl-1-oxo-3,7-diphenyl-4a,5,7,7a-tetrahydrocyclo-
1H NMR (400 MHz, CDCl3): δ = 7.34–7.45 (m, 5 H); 7.18–7.34 (m, 5 H); 4.84–4.93 (m, 1 H); 3.78 (s, 3 H); 3.42–3.55 (m, 4 H); 3.00–3.15 (m, 4 H); 2.24–2.33 (m, 1 H);
1.83 (s, 3 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.2, 168.7, 144.9, 138.2, 133.1, 128.8, 128.7, 128.6, 128.2, 128.1, 127.5, 109.8, 65.0, 53.5, 53.0, 52.1, 48.4, 42.7, 39.4, 16.6 ppm. IR (film): νmax 2954, 1739, 1539, 1437, 1262, 1100, 1010, 928 cm-1.
HRMS(ESI) calcd for C25H25O6 (M+H)+: 421.1651, Found: 421.1641; 98:2 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 11.4 min, tr (minor) = 12.7 min.
(6aR,7R,9aR)-Dimethyl 6-oxo-7-phenyl-6a,7,9,9a,10,11-hexahydrobenzo[h]cyclo- penta[c]chromene-8,8(6H)-dicarboxylate: a yellow oil; [α]D 23 (c 0.5, CHCl3) = -32.1;
1H NMR (400 MHz, CDCl3): δ = 7.50–7.56 (m, 1 H); 7.18–7.36 (m, 7 H); 7.08–7.18 (m, 1 H); 4.75 (d, J = 7.6 Hz, 1 H); 3.69 (s, 3 H); 3.53–3.61 (m, 2 H); 3.13 (s, 3 H);
2.98–3.12 (m, 1 H); 2.76–2.98 (m, 2 H); 2.33–2.46 (m, 2 H); 2.17–2.33 (m, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.4, 170.2, 168.4, 142.6, 138.0, 135.3, 128.6, 128.23, 128.15, 127.6, 127.2, 126.6, 121.5, 110.7, 65.0, 54.1, 53.0, 52.2, 48.4, 40.6, 39.1, 27.5, 24.6 ppm. IR (film): νmax 2954, 1750, 1729, 1524, 1436, 1093, 1020, 928 cm-1. HRMS(ESI) calcd for C26H25O6 (M+H)+: 433.1651, Found: 433.1649; 97:3 er as
determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 21.7 min, tr (minor) = 32.3 min.
(4aS,7R,7aR)-Dimethyl 3-(4-bromophenyl)-7-(naphthalen-2-yl)-1-oxo-4a,5,7,7a- tetrahydrocyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.00, CHCl3) = -79.8; 1H NMR (400 MHz, CDCl3): δ = 7.74–7.84 (m, 4 H); 7.36–7.54 (m, 7 H); 5.60 (d, J = 2.4 Hz, 1 H); 4.84 (d, J = 8.4 Hz, 1 H); 3.72 (s, 3 H); 3.60–3.70 (m, 2 H); 3.18 (dd, J = 13.6, 7.2 Hz, 1 H); 2.29 (dd, J = 14.0, 4.0 Hz, 1 H). 13C NMR (100 MHz, CDCl3): δ = 171.5, 170.2, 168.0, 148.3, 134.6, 133.1, 132.8, 131.7, 131.1, 128.03, 127.98, 127.8, 127.5, 126.31, 126.26, 126.10, 126.06, 123.4, 102.7, 64.9, 53.9, 53.1, 52.3, 47.6, 41.3, 36.7 ppm. IR (film): νmax 2954, 1728, 1523, 1425, 1008, 928 cm-1. HRMS(ESI) calcd for C28H24BrO6 (M+H)+: 535.0756, Found: 535.0749; 99:1 er as determined by HPLC (Chiralcel IC, 80:20 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 18.9 min, tr (minor) = 31.2 min.
(4aS,7R,7aR)-Dimethyl 3-(4-chlorophenyl)-7-(naphthalen-2-yl)-1-oxo-4a,5,7,7a- tetrahydrocyclopenta[c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.67, CHCl3) = -64.9; 1H NMR (400 MHz, CDCl3): δ = 7.79–7.82 (m, 4 H); 7.53–7.77 (m, 2H); 7.34–7.47 (m, 5H); 5.58–5.59 (m, 1H); 4.84 (d, J = 8.4 Hz, 1 H); 3.72 (s, 3 H);
3.66–3.70 (m, 1 H); 3.16–3.21 (m, 1H); 3.02 (s, 3H); 2.29 (dd, J = 13.6, 4.0 Hz, 1 H).
13C NMR (100 MHz, CDCl3): δ = 171.5, 170.2, 168.0, 148.3, 135.2, 134.6, 133.2, 132.9, 130.7, 128.8, 128.1, 128.0, 127.9, 127.5, 126.3, 126.1, 126.1, 102.6, 65.0, 53.9, 53.1, 52.3, 47.7, 41.4, 36.7. IR (film): νmax 2954, 1757, 1729, 1601, 1527, 1437, 1424, 1017, 928 cm-1. HRMS(ESI) calcd for C28H24ClO6 (M+H)+: 491.1261, Found: 491.1263; 95:5 er as determined by HPLC (Chiralcel IA, 80:20 hexanes/i-PrOH, 0.7 mL/min), tr (major)
= 47.5 min, tr (minor) = 24.3 min.
(4aS,7R,7aR)-Dimethyl 3-methyl-1-oxo-7-phenyl-4a,5,7,7a-tetrahydrocyclopenta- [c]pyran-6,6(1H)-dicarboxylate: a colorless oil; [α]D 23 (c 1.61, CHCl3) = -46.1; 1H NMR (500 MHz, CDCl3): δ = 7.20–7.38 (m, 5 H), 4.77 (d, J = 1.0 Hz, 1 H), 4.62 (d, J
= 9.5 Hz, 1 H), 3.75 (s, 3 H), 3.34–3.52 (m, 2 H), 3.12 (s, 3 H), 3.01 (dd, J = 14.0 Hz, 7.5 Hz, 1 H), 2.13 (dd, J = 14 Hz, 4.5 Hz, 1 H), 1.88 (s, 3 H). 13C NMR (125 MHz, CDCl3): δ = 171.7, 170.2, 168.8, 148.5, 137.3, 128.7, 128.2, 127.6, 102.2, 65.0, 53.5, 52.9, 52.2, 47.4, 41.1, 36.1, 18.7 ppm. IR (film): νmax 2986, 1723, 1422, 1264, 1112,
896cm-1. HRMS(ESI) calcd for C19H21O6 (M+H)+: 345.1338, Found: 345.1338; 95:5 er as determined by HPLC (Chiralcel ID, 80:20 hexanes/i-PrOH, 0.7 mL/min), tr (major)
= 23.5 min, tr (minor) = 26.9 min.
(4aS,7R,7aR)-Diethyl 1-oxo-3,7-diphenyl-4a,5,7,7a-tetrahydrocyclopenta- [c]pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 2.01, CHCl3) = -10.0; 1H NMR (400 MHz, CDCl3): δ = 7.58–7.61 (m, 2H); 7.23–7.39 (m, 8H); 5.56 (d, J= 3.2 Hz, 1H); 4.70 (d, J= 4.8 Hz, 1H); 4.18 (q, J= 6.8 Hz, 2H); 3.74 (dd, J= 14.0, 7.2 Hz, 1H); 2.29 (dd, J= 14.0, 4.0 Hz, 1H); 1.20 (t, J= 7.2 Hz, 3H); 0.75 (t, J= 7.2 Hz, 3H).
13C NMR (100 MHz, CDCl3): δ = 171.1, 169.9, 168.5, 149.2, 137.5, 132.2, 129.2, 128.9, 128.5, 128.2, 127.7, 124.8, 102.3, 65.0, 61.9, 61.5, 53.5, 47.9, 41.3, 36.7, 13.9, 13.3. IR (film): νmax 2954, 1766, 1722, 1520, 1423, 1075, 928 cm-1. HRMS(ESI) calcd for
C26H27O6 (M+H)+: 435.1808, Found: 435.1805; 96:4 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 10.0 min, tr (minor) = 11.9 min.
(4aS,7R,7aR)-Dibenzyl 1-oxo-3,7-diphenyl-4a,5,7,7a-tetrahydrocyclopenta[c]- pyran-6,6(1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.39, CHCl3) = +26.2; 1H NMR (400 MHz, CDCl3): δ = 7.51–7.54 (m, 2H); 7.11–7.38 (m, 16H); 6.84–6.86 (m, 2H);
5.45–5.46 (m, 1H); 5.12 (d, J= 12.4 Hz, 1H); 4.96 (d, J= 12.0 Hz, 1H); 4.71–4.75 (m, 2H); 4.18 (d, J= 12.4 Hz, 1H); 3.55–3.58 (m, 2H); 3.15 (dd, J= 13.6, 7.2 Hz, 1H); 2.32 (dd, J= 13.6, 7.2 Hz, 1H). 13C NMR (100 MHz, CDCl3): δ = 170.8, 169.7, 168.3, 149.3, 137.1, 135.1, 134.6, 132.2, 129.2, 128.9, 128.5, 128.4, 128.3, 128.3, 128.2, 128.0, 127.9, 124.9, 102.2, 67.8, 67.4, 65.2, 53.7, 47.9, 41.3, 36.7. IR (film): νmax 2954, 1767, 1721, 1419, 1025, 928 cm-1. HRMS(ESI) calcd for C36H31O6 (M+H)+: 559.2121, Found:
559.2118; 96:4 er as determined by HPLC (Chiralcel IB, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 14.4 min, tr (minor) = 16.5 min.
(4aS,7R,7aR)-Dibenzyl 7-(4-chlorophenyl)-1-oxo-3-phenyl-4a,5,7,7a-tetrahydro- cyclopenta[c]pyran-6,6(1H)-dicarboxylate: a white solid; [α]D 23 (c 1.55, CHCl3) = +4.7; 1H NMR (400 MHz, CDCl3): δ = 7.50–7.53 (m, 2H); 7.34–7.37 (m, 3H); 7.22–
7.32 (m, 8H); 7.15 (d, J= 8.4 Hz, 4H); 6.86 (d, J= 6.8 Hz, 2H); 5.45 (d, J= 3.2 Hz, 1H); 5.13 (d, J= 12.0 Hz, 1H); 5.01 (d, J= 12.0 Hz, 1H); 4.62 (d, J= 10.0 Hz, 1H);
4.37 (d, J= 12.0 Hz, 1H); 3.48–3.58 (m, 2H); 3.13 (dd, J= 14.0, 7.6 Hz, 1H); 2.32 (dd, J= 14.0, 4.4 Hz, 1H). 13C NMR (100 MHz, CDCl3): δ = 170.7, 169.6, 168.0, 149.2,
124.8, 102.2, 67.9, 67.6, 64.9, 52.9, 47.6, 41.3, 36.5, 29.7. IR (film): νmax 2954, 1762, 1729, 1515, 1437, 1275, 1215, 1016, 929 cm-1. IR (film): νmax 2954, 1724, 1525, 1424, 1015, 928 cm-1. HRMS(ESI) calcd for C36H30ClO6 (M+H)+: 597.1731, Found:
597.1730; 97:3 er as determined by HPLC (Chiralcel IA, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 16.7 min, tr (minor) = 22.7 min.
(4aS,8R,8aR)Dimethyl 1oxo3,8diphenyl5,6,8,8atetrahydro1Hisochromene -7,7(4aH)-dicarboxylate: a yellow oil; [α]D 23 (c 2.10, CHCl3) = +15.6; 1H NMR (400 MHz, CDCl3): δ = 7.57–7.60 (m, 2H); 7.32–7.41 (m, 4H); 7.21–7.27 (m, 4H); 5.57 (dd, J= 2.0, 1.6 Hz, 1H); 4.03 (dd, J= 12.0, 4.8 Hz, 1H); 3.70 (s, 3H); 3.45 (d, J= 12.0 Hz, 1H); 3.33 (s, 3H); 3.27 (d, J= 2.4 Hz, 1H); 2.26–2.35 (m, 1H); 1.93–1.97 (m, 1H);
1.24–1.87 (m, 1H). 13C NMR (100 MHz, CDCl3): δ = 171.0, 170.2, 168.0, 150.7, 136.5, 132.0, 130.3, 129.1, 128.6, 127.9, 127.7, 124.6, 103.2, 59.5, 52.2, 45.9, 41.7, 31.6, 30.0, 25.3. IR (film): νmax 2954, 1773, 1731, 1543, 1420, 928 cm-1. HRMS(ESI) calcd for C25H24O6Na (M+ Na)+: 443.1471, Found: 443.1471; 96:4 er as determined by HPLC (Chiralcel IB, 95:5 hexanes/i-PrOH, 0.7 mL/min), tr1 (major) = 21.9 min, tr1(minor) = 23.7 min tr2 (major) = 25.4 min, tr 2(minor) = 33.5 min.
(4aS,8R,8aR)-Dimethyl 8-(4-chlorophenyl)-1-oxo-3-phenyl-5,6,8,8a-tetrahydro- 1H-isochromene-7,7(4aH)-dicarboxylate: a yellow oil; [α]D 23 (c 0.5, CHCl3) = -24.1;
1H NMR (400 MHz, CDCl3): δ = 7.57–7.60 (m, 2H); 7.38–7.39 (m, 5H); 7.22 (d, J= 8.8 Hz, 2H); 5.57 (dd, J= 2.0, 1.5 Hz, 1H); 3.96–4.01 (m, 1H); 3.72 (s, 3H); 3.39 (d, J
= 8.4 Hz, 1H); 3.37 (s, 3H); 3.29 (d, J= 2.8 Hz, 1H); 2.27–2.33 (m, 2H); 1.93–1.98 (m, 1H); 1.80–1.86 (m, 1H). 13C NMR (100 MHz, CDCl3): δ = 170.8, 170.0, 167.7, 150.7, 134.8, 133.8, 131.8, 131.7, 129.2, 128.6, 127.9, 124.5, 103.0, 59.5, 52.3, 45.3, 41.6, 31.6, 29.9, 25.2. IR (film): νmax 2954, 1767, 1730, 1517, 1424, 1016, 928 cm-1. HRMS(ESI) calcd for C25H24ClO6 (M+H)+: 455.1261, Found: 455.1242; 95:5 er as determined by HPLC (Chiralcel ID, 80:20 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 18.4 min, tr (minor) = 21.7 min.
(4aS,8R,8aR)-Dimethyl 8-(4-isopropylphenyl)-1-oxo-3-phenyl-5,6,8,8a-tetrahydro-1H-isochromene-7,7(4aH)-dicarboxylate: a yellow oil; [α]D 23 (c 1.00, CHCl3) = -65.8; 1H NMR (400 MHz, CDCl3): δ = 7.58–7.60 (m, 2H); 7.33–7.41 (m, 3H); 7.28 (s, 2H); 7.09 (d, J= 4.4 Hz, 2H); 5.56 (d, J= 0.8 Hz, 1H); 4.02 (dd, J= 12.0,
2.25–2.35 (m, 2H); 1.81–1.96 (m, 2H); 1.21 (s, 3H); 1.19 (s, 3H). 13C NMR (100 MHz, CDCl3): δ = 171.0, 170.2, 168.0, 150.6, 148.2, 133.7, 132.1, 130.1, 129.1, 128.5, 125.7, 124.6, 103.2, 59.6, 52.1, 52.0, 45.6, 41.7, 33.6, 31.7, 30.0, 25.4, 23.9, 23.8. IR (film):
νmax 2954, 2928 1514, 1435, 1021, 928 cm-1. HRMS(ESI) calcd for C28H31O6 (M+H)+:
463.2121, Found: 463.2121; 94:6 er as determined by HPLC (Chiralcel ODH, 98:2 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 28.9 min, tr (minor) = 41.2 min.
(4aS,8S,8aR)-Dimethyl 1-oxo-3-phenyl-8-(thiophen-2-yl)-5,6,8,8a-tetrahydro-1H-isochromene-7,7(4aH)-dicarboxylate: a yellow oil; [α]D 23 (c 1.00, CHCl3) = +231.1;
1H NMR (400 MHz, CDCl3): δ = 7.55–7.57 (m, 2H); 7.31–7.37 (m, 3H); 7.19 (d, J= 4.8 Hz, 1H); 7.09–7.10 (m, 1H); 6.95 (d, J= 5.2, 3.6 Hz, 1H); 5.64 (s, 1H); 4.84 (d, J= 1.6 Hz, 1H); 3.78 (s, 3H); 3.49 (s, 3H); 3.19–3.21 (m, 2H); 2.50–2.58 (m, 1H); 2.38–
2.42 (m, 1H); 2.17–2.22 (m, 1H); 1.23–1.33 (m, 1H). 13C NMR (100 MHz, CDCl3): δ
= 170.9, 169.2, 167.4, 149.4, 137.8, 132.1, 129.9, 129.0, 128.4, 126.1, 125.0, 124.5, 105.2, 59.4, 53.1, 52.5, 44.1, 40.0, 30.3, 28.4, 26.3. IR (film): νmax 2954, 1731, 1525, 1427, 1219, 1159, 1019, 928 cm-1. HRMS(ESI) calcd for C23H23O6S (M+H)+: 427.1215, Found: 427.1206; 95:5 er as determined by HPLC (Chiralcel ODH, 92:8 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 23.1 min, tr (minor) = 27.6 min.
(4aS,7S,8R,8aR)-7-Nitro-3,8-diphenyl-4a,5,6,7,8,8a-hexahydro-1H-isochromen-1-one: a white solid; [α]D 23 (c 1.20, CHCl3) = -43.0; 1H NMR (400 MHz, CDCl3): δ = 7.68 (dd, J= 7.2, 1.6 Hz, 2H); 7.43–7.47 (m, 3H); 7.28–7.34 (m, 3H); 7.18 (d, J= 7.2 Hz, 2H); 5.63 (s, 1H); 4.77–4.84 (m, 1H); 3.54 (t, J= 9.0 Hz, 1H); 3.28 (s, 1H); 3.01 (dd, J= 9.0, 0.9 Hz, 1H); 2.19–2.39 (m, 3H); 1.92–2.01 (m, 1H). 13C NMR (100 MHz, CDCl3): δ = 166.5, 151.2, 135.4, 131.7, 129.6, 129.1, 128.7, 128.6, 127.8, 124.7, 102.3, 88.7, 46.5, 43.8, 31.3, 27.7, 27.1. IR (film): νmax 2954, 1772, 1558, 1215, 1047, 1014, 928 cm-1. HRMS(ESI) calcd for C21H20NO4 (M+H)+: 350.1392, Found: 350.1391;
87:13 er as determined by HPLC (Chiralcel IA, tr (major) = 37.6 min, tr (minor) = 22.5 min hexanes/i-PrOH, 0.7 mL/min), tr (major) = 19.3 min, tr (minor) = 21.2 min.
(4aS,7S,8R,8aR)-8-(4-chlorophenyl)-7-nitro-3-phenyl-4a,5,6,7,8,8a-hexahydro-1H-isochromen-1-one: a yellow solid; [α]D 23 (c 1.75, CHCl3) = +0.8; 1H NMR (400 MHz, CDCl3): δ = 7.65 – 7.68 (m, 2 H); 7.42 – 7.47 (m, 3 H); 7.29 (d, J = 8.4 Hz, 2 H);
5.62 (t, J = 0.4 Hz, 1 H); 4.70 – 4.77 (m, 1 H); 3.82 (s, 3 H); 3.71 (s, 3 H); 3.48 – 3.64 (m, 2 H); 3.13 (s, 3 H); 3.04 – 3.15 (m, 1 H); 2.26 (dd, J1 = 14.0 Hz, J2 = 4.4 Hz, 1 H).
13C NMR (100 MHz, CDCl3): δ = 166.3, 151.2, 134.6, 134.0, 131.5, 129.7, 129.4, 129.2, 128.8, 124.6, 102.1, 88.6, 46.3, 43.2, 31.2, 27.6, 26.9 ppm. IR (film): νmax 2954, 2927,
2854, 1762, 1558, 1525, 1465, 1419, 928 cm-1. HRMS(ESI) calcd for C21H19O4NCl (M+ H)+: 384.1003, Found: 384.1004.
(4aS,7S,8R,8aR)-3-(furan-3-yl)-5,5-dimethyl-7-nitro-8-phenyl-4a,5,6,7,8,8a-hexahydro-1H-isochromen-1-one: a yellow oil; [α]D 23 (c 1.73, CHCl3) = +3.6; 1H NMR (400 MHz, CDCl3): δ = 7.71 (s, 1H); 7.47 (s, 1H); 7.31–7.35 (m, 3H); 7.26–7.30 (m, 2H); 6.59 (d, J= 1.2 Hz, 1H); 5.50 (s, 1H); 4.97–5.04 (m, 1H); 3.53 (t, J= 12.0 Hz, 1H); 3.22–3.26 (m, 1H); 2.76 (d, J= 2.0 Hz, 1H); 2.14 (t, J= 4.4 Hz, 1H); 2.04 (dd, J= 12.0, 4.0 Hz, 1H); 1.22 (s, 6H). 13C NMR (100 MHz, CDCl3): δ = 166.7, 145.8, 144.1, 140.4, 135.4, 129.1, 128.7, 128.6, 127.8, 119.5, 107.0, 98.0, 86.8, 44.4, 43.6, 41.4, 39.9, 33.5, 297, 28.2, 26.1. IR (film): νmax 2927, 1768, 1558, 1517, 1419, 1018, 929 cm-1. HRMS(ESI) calcd for C21H22NO5 (M+H)+: 368.1498, Found: 368.14987; 89:11 er as determined by HPLC (Chiralcel IA, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 32.3 min, tr (minor) = 19.8 min.
(3R,4aS,7R,7aR)-Dimethyl 1-oxo-3,7-diphenylhexahydrocyclopenta[c]pyran-6,6 (1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.00, CHCl3) = -10.3; 1H NMR (400 MHz, CDCl3): δ = 7.29–7.41 (m, 5H); 7.22–7.28 (m, 5H); 5.59 (dd, J= 7.6, 2.8 Hz, 1H); 4.34 (d, J= 10.4 Hz, 1H); 3.74 (s, 3H); 3.47 (t, J= 10.4 Hz, 1H); 3.33 (s, 3H); 3.19 (dd, J= 8.4, 2.0 Hz, 1H); 2.89 (dd, J= 14.0, 8.4 Hz, 1H); 2.31–2.38 (m, 1H); 1.91–1.99 (m, 2H).
13C NMR (100 MHz, CDCl3): δ = 171.8, 171.3, 170.5, 138.9, 137.3, 128.8, 128.6, 128.2, 128.1, 127.7, 125.5, 65.2, 54.8, 52.8, 52.1, 47.8, 41.6, 35.5, 32.6. IR (film): νmax 2952, 1730, 1520, 1436, 1271, 1050, 928 cm-1. HRMS(ESI) calcd for C24H23O7 (M+ H)+: 423.1444, Found: 423.1440; 96:4 er as determined by HPLC (Chiralcel IA, 90:10 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 32.2 min, tr (minor) = 44.6 min.
(3S,4aS,7R,7aR)-Dimethyl 1-oxo-3,7-diphenylhexahydrocyclopenta[c]pyran-6,6 (1H)-dicarboxylate: a yellow oil; [α]D 23 (c 1.1, CHCl3) = -11.0; 1H NMR (400 MHz, CDCl3): δ = 7.21–7.39 (m, 10H); 5.29 (dd, J= 11.2, 1.6 Hz, 1H); 4.73 (d, J= 7.2 Hz, 1H); 3.74 (s, 3H); 3.48–3.54 (m, 2H); 3.25 (s, 3H); 2.89 (dd, J= 13.6, 2.8 Hz, 1H);
2.37–2.41 (m, 1H); 1.77 (dd, J= 16.8, 8.8 Hz, 1H); 1.59–1.68 (m, 1H). 13C NMR (100 MHz, CDCl3): δ = 172.9, 171.3, 170.8, 139.3, 138.9, 128.7, 128.5, 128.2, 127.3, 126.0, 80.3, 65.5, 52.8, 52.6, 52.1, 48.8, 42.3, 38.1, 36.3. IR (film): νmax 2952, 1730, 1520, 1436, 1271, 1050, 928 cm-1. HRMS(ESI) calcd for C24H23O7 (M+ H)+: 423.1444,
Found: 423.1440; 96:4 er as determined by HPLC (Chiralcel IA, 80:20 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 45.3 min, tr (minor) = 25.2 min.
(1R,3aS,4R,6aR)-Dimethyl 1-benzoyl-3-oxo-4-phenyltetrahydro-1H-cyclopenta[c]
furan-5,5(3H)-dicarboxylate: a yellow oil; [α]D 23 (c 0.5, CHCl3) = -43.3; 1H NMR (400 MHz, CDCl3): δ = 7.98–8.00 (m, 2H); 7.67 (d, J= 7.6 Hz, 1H); 7.54–7.57 (m, 2H);
7.18–7.30 (m, 5H); 5.52 (d, J= 2.4 Hz, 1H); 4.53 (d, J= 4.0 Hz, 1H); 3.76–3.80 (m, 4H); 3.43 (dd, J= 9.2, 4.0 Hz, 1H); 3.22 (s, 3H); 3.10–3.15 (m, 1H); 2.29–2.33 (m, 1H).
13C NMR (100 MHz, CDCl3): δ = 193.9, 177.4, 170.8, 169.4, 138.8, 134.5, 133.5, 129.2, 128.8, 128.5, 128.2, 127.7, 81.7, 67.3, 54.1, 53.2, 52.3, 50.2, 42.9, 39.9, 29.7. IR (film):
νmax 2954, 1786, 1730, 1599, 1433, 1216, 1022 cm-1. HRMS(ESI) calcd for C24H23O7
(M+H)+: 423.1444, Found: 423.1440; 96:4 er as determined by HPLC (Chiralcel OJH, 70:30 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 11.3 min, tr (minor) = 15.6 min.
(1S,3aS,4R,6aR)-Dimethyl 1-benzoyl-3-oxo-4-phenyltetrahydro-1H-cyclopenta [c]furan-5,5(3H)-dicarboxylate: a yellow oil; [α]D 23 (c 0.5, CHCl3) = -49.2; 1H NMR (400 MHz, CDCl3): δ = 8.02 (d, J= 7.6 Hz, 2H); 7.69 (d, J= 7.6 Hz, 1H); 7.54–7.66
(m, 2H); 7.22–7.32 (m, 5H); 5.94 (d, J= 6.8 Hz, 1H); 4.55 (d, J= 4.8 Hz, 1H); 4.23 (t, J= 11.2 Hz, 1H); 3.69 (s, 3H); 3.56 (dd, J= 8.8, 4.4 Hz, 1H); 3.11 (s, 3H); 2.41 (dd, J
= 14.4, 4.0 Hz, 1H); 1.84 (dd, J= 14.4, 6.4 Hz, 1H);. 13C NMR (100 MHz, CDCl3): δ = 192.3, 176.6, 170.1, 170.0, 138.9, 134.5, 134.2, 129.9, 128.4, 128.2, 128.1, 127.6, 79.6, 67.7, 53.0, 52.9, 52.7, 52.1, 44.2, 35.9. IR (film): νmax 2954, 1786, 1730, 1599, 1433, 1216, 1022 cm-1. HRMS(ESI) calcd for C24H23O7 (M+H)+: 423.1444, Found: 423.1440;
96:4 er as determined by HPLC (Chiralcel OJH, 70:30 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 40.0 min, tr (minor) = 62.3 min.
(1R,2S,6R)-Methyl 2-(2-(furan-3-yl)-2-oxoethyl)-3,3-dimethyl-6-phenylcyclohexanecarboxylate: a white solid; [α]D 23 (c 0.5, CHCl3) = -78; 1H NMR (400 MHz, CDCl3): δ = 8.09 (dd, J= 1.2, 0.8 Hz, 1H); 7.43 (t, J= 1.6 Hz, 1H); 7.14–
7.25 (m, 5H); 6.77 (q, J= 0.8 Hz, 1H); 3.33 (s, 3H); 3.28–3.21 (m, 1H); 3.11 (dd, J= 18.4, 4.4 Hz, 1H); 2.94 (dd, J= 18.4, 6.0 Hz, 1H); 2.80–2.84 (m, 2H); 1.52–1.72 (m, 3H); 1.31–1.35 (m, 1H); 1.25 (s, 3H); 0.88 (s, 3H). 13C NMR (100 MHz, CDCl3): δ = 193.4, 174.7, 146.7, 144.8, 144.0, 128.4, 127.6, 127.2, 126.3, 108.7, 51.4, 47.4, 40.9, 39.7, 36.9, 34.1, 33.2, 29.3, 26.4, 23.5. HRMS(ESI) calcd for C22H27O4NCl (M+ H)+: 355.1904, Found: 355.1908. 90.5:9.5 er as determined by HPLC (Chiralcel ODH, 98:02 hexanes/i-PrOH, 0.7 mL/min), tr (major) = 14.5 min, tr (minor) =11.9 min.
(S)-5-Benzyl-2-(2,6-dimethoxyphenyl)-6,6-diethyl-6,8-dihydro-5H-[1,2,4]triazolo[3,4-c][1,4]oxazin-2-ium tetrafluoroborate a yellow solid; [α]D 23 (c 1.06, CHCl3) = +3.7; 1H NMR (400 MHz, CDCl3): δ = 8.44 (s, 1H); 7.43 (t, J= 8.8 Hz, 1H); 7.19–7.30 (m, 3H); 7.12 (d, J= 7.2 Hz, 2H); 6.62 (d, J= 8.8 Hz, 2H); 5.25 (dd, J
= 10.8, 4.4 Hz, 1H); 5.11 (d, J= 17.2 Hz, 1H); 4.92 (d, J= 17.2 Hz, 1H); 3.80 (s, 6H);
3.43 (dd, J= 14.0, 4.4 Hz, 1H); 2.92 (dd, J= 14.0, 11.2 Hz, 1H); 1.78–2.04 (m, 3H);
1.58 (dd, J= 15.6, 7.2 Hz, 2H); 1.10 (t, J= 7.6 Hz, 3H); 1.00 (t, J= 7.6 Hz, 3H). 13C NMR (100 MHz, CDCl3): δ = 155.4, 148.3, 144.9, 134.4, 133.5, 129.9, 129.2, 127.9, 112.0, 104.3, 78.9, 61.8, 56.5, 56.4, 36.8, 25.3, 21.9, 7.3, 6.9 ppm. IR (film): νmax 1590, 1525, 1419, 1064, 1034, 928, 850 cm-1. HRMS(ESI) calcd for C24H30O3N3 (M)+: 408.2287, Found: 408.2287.
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